R-parity Violation in Neutralino Decays at an e \gamma Collider

At an e-\gamma collider, a selectron \tilde{e}_{L,R} may be produced in association with a (lightest) neutralino \tilde{\chi}_1. Decay of the selectron may be expected to yield a final state with an electron and another \tilde{\chi}_1. If R-parity is violated, these two neutralinos will decay, giving rise to distinctive signatures, which are identified and studied.Comment: LaTeX, 17 pages, 4 figure

Top off the unparticle

The existence of an exactly scale invariant sector possessing a non-trivial infrared fixed point at a higher energy scale and its possible communication with the Standard Model particles through a heavy messenger sector has been shown to lead to curious unparticle effects. We demonstrate that top physics at the Tevatron can already constrain such theories. We also consider possible improvements at the LHC and delineate some striking signatures.Comment: 5 page